edited January 24
I have come to the conclusion that the sleep tracker on the Tom Tom Runner 3 is inaccurate and could be a manufacturing fault on all Tom Tom devices.
It is just a poor algorithm. All the watch is using to detect sleep is movement; when you stop moving for some specified period of time (likely around 30 minutes) it assumes you are asleep and assumes you are awake when it gets a sustained period of movement. If 25 minutes into the 30 minute detection period you suddenly move a bit it is going to start over the 30 minute evaluation period again. So if you are a fairly restless sleeper and move around a lot there is a chance that it will not be able to accurately detect your sleep patterns. In this case you can take it off your wrist and put it on a side table (make sure it is someplace that will not get moved or shaken) and it will detect you as asleep. Pick it up when you wake up to show you are awake. You will unfortunately then lose the 24/7 HR but will get sleep tracking. I would say it is fairly accurate in general. It seems to catch me falling asleep and waking up fairly well, although I do notice if I wake up 30 minutes before my alarm and fall back asleep it sometimes will not count the last 30 minutes. This may be because I was restless and was not still enough to register as sleep or I was awake before the evaluation period was finished so it never registered me as back asleep. You can test it by taking it off and leaving it somewhere where it will not be disturbed and see if it goes into sleep tracking eventually.
Since TT has left the sports watch business and is no longer producing new watches this is not going to change in the future. We are going to have to live with it.
I imagine this is not what you were hoping to hear but let me know if this answered your question. If it did, please mark it as a solution so other can look for it if they have the same question.
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